Reasons for manipulating nickel ion concentration in catholyte

The concentration of nickel ions in the solution has a very large interference with the volatilization potential of nickel at the cathode. In order to better obtain products with higher purity, there are high regulations on the concentration value in production. Let us briefly explain to you The reason for controlling the concentration of nickel ions in the catholyte.

If the concentration of nickel ions is too low, it will promote the volatilization of hydrogen at the cathode, resulting in an increase in the pH value of part of the cathode area, resulting in the deposition of Ni(OH)2, which interferes with the quality of the product; if the concentration of nickel ions is too high, the grains of the nickel plate will be unsmooth, Small bumps are caused on the surface, and the natural nickel ion concentration is too high, which is not economical development.

In order to better ensure product quality in production, the current volume of electrowinning production will be sharply adjusted according to the different nickel ion concentrations, so as to achieve an effective balance point, to avoid high current control, low nickel ions or electric current. The flow rate is low and the nickel ions are high, resulting in long pores or granulation on the surface of the nickel electrodeposited, which interferes with the quality of the product.

In the production process, the actual operation must be strictly completed according to the regulations. The concentration value can be slightly wrong but not very different, so as to avoid the product quality being disturbed due to the mismatch between the current amount and the concentration value of the main metal material.

Although the harmful impurity ions in the nickel salt aqueous electrolyte can be chemically removed as much as possible, the hydrogen ions in it will always exist, and it is because of this that the whole process of the cathode of nickel electrolysis becomes more Complex. During point solution, hydrogen ions will be analyzed from the catholyte earlier than nickel, and the surface layer of nickel electrodeposited will cause many pores. When the pH value is high, it will cause Ni(OH)2 deposition, which will result in obtaining The cathode nickel is not very tight. Therefore, the PH value of the catholyte must be strictly controlled according to the corresponding actual operating regulations, and the PH value during production is usually controlled at around pH 3.03.8.